"Global warming" redirects here. For other uses, see Climate change

Aerosols and clouds
Air pollution, in the form of aerosols, affects the climate on a large scale.^[88] Aerosols scatter and absorb solar radiation. From 1961 to 1990, a gradual reduction in the amount of sunlight reaching the Earth's surface was observed. This phenomenon is popularly known as global dimming,^[89] and is attributed to aerosols produced by dust, pollution and combustion of biofuels and fossil fuels.^{[90][91][92][93][94]} Globally, aerosols have been declining since 1990 due to pollution controls, meaning that they no longer mask greenhouse gas warming as much.^[95]
Aerosols also have indirect effects on the Earth's radiation budget. Sulfate aerosols act as cloud condensation nuclei and lead to clouds that have more and smaller cloud droplets. These clouds reflect solar radiation more efficiently than clouds with fewer and larger droplets.^[96] They also reduce the growth of raindrops, which makes clouds more reflective to incoming sunlight.^[97] Indirect effects of aerosols are the largest uncertainty in radiative forcing.^[98]
While aerosols typically limit global warming by reflecting sunlight, black carbon in soot that falls on snow or ice can contribute to global warming. Not only does this increase the absorption of sunlight, it also increases melting and sea-level rise.^[99] Limiting new black carbon deposits in the Arctic could reduce global warming by 0.2 °C by 2050.^[100]
Land surface changes
The rate of global tree cover loss has approximately doubled since 2001, to an annual loss approaching an area the size of Italy.^[101]
Humans change the Earth's surface mainly to create more agricultural land. Today, agriculture takes up 34% of Earth's land area, while 26% is forests, and 30% is uninhabitable (glaciers, deserts, etc.).^[102] The amount of forested land continues to decrease, which is the main land use change that causes global warming.^[103] Deforestation releases CO₂ contained in trees when they are destroyed, plus it prevents those trees from absorbing more CO₂.^[23] The main causes of deforestation are: permanent land-use change from forest to agricultural land producing products such as beef and palm oil (27%), logging to produce forestry/forest products (26%), short term shifting cultivation (24%), and wildfires (23%).^[104]
The type of vegetation in a region affects the local temperature. It impacts how much of the sunlight gets reflected back into space (albedo), and how much heat is lost by evaporation. For instance, the change from a dark forest to grassland makes the surface lighter, causing it to reflect more sunlight. Deforestation can also affect temperatures by modifying the release of chemical compounds that influence clouds, and by changing wind patterns.^[105] In tropic and temperate areas the net effect is to produce significant warming, while at latitudes closer to the poles a gain of albedo (as forest is replaced by snow cover) leads to a cooling effect.^[105] Globally, these effects are estimated to have led to a slight cooling, dominated by an increase in surface albedo.^[106] According to FAO, forest degradation aggravates the impacts of climate change as it reduces the carbon sequestration abilities of forests. Indeed, among their many benefits, forests also have the potential to reduce the impact of high temperatures.^[107]